#
# -*- coding: utf-8 -*-
# Copyright 2019 Red Hat
# GNU General Public License v3.0+
# (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
"""
The junos interfaces fact class
It is in this file the configuration is collected from the device
for a given resource, parsed, and the facts tree is populated
based on the configuration.
"""
from __future__ import absolute_import, division, print_function
__metaclass__ = type

from copy import deepcopy

from ansible.module_utils._text import to_bytes
from ansible.module_utils.network.common import utils
from ansible.module_utils.network.junos.argspec.interfaces.interfaces import InterfacesArgs
from ansible.module_utils.six import string_types
try:
    from lxml import etree
    HAS_LXML = True
except ImportError:
    HAS_LXML = False


class InterfacesFacts(object):
    """ The junos interfaces fact class
    """
    def __init__(self, module, subspec='config', options='options'):
        self._module = module
        self.argument_spec = InterfacesArgs.argument_spec
        spec = deepcopy(self.argument_spec)
        if subspec:
            if options:
                facts_argument_spec = spec[subspec][options]
            else:
                facts_argument_spec = spec[subspec]
        else:
            facts_argument_spec = spec

        self.generated_spec = utils.generate_dict(facts_argument_spec)

    def populate_facts(self, connection, ansible_facts, data=None):
        """ Populate the facts for interfaces

        :param connection: the device connection
        :param data: previously collected configuration as lxml ElementTree root instance
                     or valid xml sting
        :rtype: dictionary
        :returns: facts
        """
        if not HAS_LXML:
            self._module.fail_json(msg='lxml is not installed.')

        if not data:
            config_filter = """
            <configuration>
                <interfaces/>
            </configuration>
            """
            data = connection.get_configuration(filter=config_filter)

        if isinstance(data, string_types):
            data = etree.fromstring(to_bytes(data, errors='surrogate_then_replace'))

        resources = data.xpath('configuration/interfaces/interface')

        objs = []
        for resource in resources:
            if resource is not None:
                obj = self.render_config(self.generated_spec, resource)
                if obj:
                    objs.append(obj)
        facts = {}
        if objs:
            facts['interfaces'] = []
            params = utils.validate_config(self.argument_spec, {'config': objs})
            for cfg in params['config']:
                facts['interfaces'].append(utils.remove_empties(cfg))
        ansible_facts['ansible_network_resources'].update(facts)

        return ansible_facts

    def render_config(self, spec, conf):
        """
        Render config as dictionary structure and delete keys
          from spec for null values

        :param spec: The facts tree, generated from the argspec
        :param conf: The ElementTree instance of configuration object
        :rtype: dictionary
        :returns: The generated config
        """
        config = deepcopy(spec)
        config['name'] = utils.get_xml_conf_arg(conf, 'name')
        config['description'] = utils.get_xml_conf_arg(conf, 'description')
        mtu = utils.get_xml_conf_arg(conf, 'mtu')
        config['mtu'] = int(mtu) if mtu else None
        config['speed'] = utils.get_xml_conf_arg(conf, 'speed')
        config['duplex'] = utils.get_xml_conf_arg(conf, 'link-mode')
        config['hold_time']['down'] = utils.get_xml_conf_arg(conf, 'hold-time/down')
        config['hold_time']['up'] = utils.get_xml_conf_arg(conf, 'hold-time/up')
        disable = utils.get_xml_conf_arg(conf, 'disable', data='tag')
        if disable:
            config['enable'] = False
        else:
            config['enable'] = True
        return utils.remove_empties(config)
